Eotary engine



(No Model.) 4 Sheets-Sheet 1.

T. A. HEARSON.

ROTARY ENGINE.

Patented July 1, 1884.

dm/U/W Jam N PETERS mmumnm m hu 'uhm on u c 4 Sheets-Sheet 2.

(No Model) T. A. HEARSON.

ROTARY ENGINE. V

Patented July 1, 1884.

(No Model.) 4 Sheets-Sheet 3.

, T. A--. HEARSON.

ROTARY ENGINE.

No. 301,235. atented July- 1, 1884.

Wo'frzeww M d I x/ gf1ganfar 4 Sheets-Sheet 4.

No Model.)

T. A. HEARSON.

ROTARY ENGINE.

PatentedJuly 1', 1.884.

Wrze 6 6 Warren Starts Parent tribe".

THOMAS ALFRED HEARSON, OF XVESTCOMBE PARK ROAD, BLAGKHEATH, COUNTY OF KENT, ENGLAND.

ROTARY ENGlNE.

SPECIFICATION forming part of Letters Patent No. 301,235, dated July 1, 188%.

Application filed October 8, 1883. (No model.) Patented in England March 1, 1883, No. 1,118; in France August 28. 1883, No. 157,267; in Belgium August 30, I883, N062,456, and in Germany September 2, 1883.

To all whom it may concern.-

Be it known that I, THOMAS ALFRED HEAR- soN, a subject of the Queen of Great Britain, residing at b VVestcombe Park Road, Blackheath, in the county of Kent, England, have invented certain new and useful Improvements in Rotary Engines and Governors and Apparatus Connected Therewith, (for which I have received Letters Patent in Great Britain, No. 1,118, dated March 1, 1883; in France, No. 157,267, dated August 28, 1883; in Belgium, No. 62, 156, dated August 30, 1883, and in Germany, dated September 2, 1883,) of which the following is a specification.

The chief object of this invention is to pro vide an engine in which the moving parts shall not be subjected to the great rate of change of velocity which occurs on the reversal of the stroke of the ordinary reciprocating engine, so that, a very great reduction in the magnitude of the forces due to change of momentum being made,a very high speed of revolution may be easily obtained. The process of the ordinary reciprocating engine has been adopted under modified circumstancesthat is to say, the steam or working fluid is admitted to one end of a work-developing chamber at a time when a piston or moving diaphragm is adjacent to that 'end. The piston is urged through the chamber againstaresistance. On the completion of the stroke the steam is admitted between the piston and the other end of the chamber, so as to drive it through the chamber in the reverse direction, and so on alternately. Now, according to this invention the chamber is a portion of an annular space within a cylinder, and the cylinder is mounted on a shaft, so that it may revolve. The piston-diaphragm moves coaxially with it, the relative movement of piston and chanr her being that of a repeated angular oscilla' tion. Further, the engine is so arranged that while the annular chamber revolves at a uniform speed, the piston-diaphragm revolves also, but with varying speed, alternately faster and slower than the chamber. By this means the repeated sweeping of the piston through the chamber from end to end is effected without any reversal of its absolute motion. This movement may be compared with that of the piston of a locomotive-engine, which, when 1 running, is always moving forward, but with varying velocity-in one stroke faster, in the next slower, than the cylinder and train. The engine may be used as a motive-power engine or as a pump for exhausting or forcing fluids.

In order that my said invention may be most fully understood and readily carried into effect, I will proceed to describe the drawings hereunto annexed.

In the drawings, Figure 1 is a side elevation, partly in section, of an engine constructed according to my invention. Fig. 2 is a transverse section. Fig. 3 is an end elevation with the end frame removed, and Fig. 4 is a plan of the same. Figs. 5, 6, and 7 are separate views of some of the parts. Fig. 8 is an elevation, and Fig. 9 is a plan, of the linkage which I employ when coupling two engines together.

The annular space previously mentioned, or, as in the actual construction, the annular spaces are obtained in the following manner: A cylinder, after it has been truly bored or turned, is divided into two, three, four, or more compartments by radial sectors, which are secured to the cylinder at ends, and also at the cylindrical surface by bolts, so as to pro vide steam-tight divisions at exactly equal angular distances apart.

The sectors (four in number) are'lettered S in Fig. 2, which is a vertical section taken one half through the cylinder, and the other half shows the cylinder end with the cover removed. The sectors extend far enough into 85 the cylinder to touch a comparatively large central boss, B, concentricwith the cylinder. Radiating from the central boss and east with it are four piston-sectors lettered It, two of which are shown in section, and two not so. 0 These pistonsectors extend outward sufficiently, and have a sufficient length, to touch the cylinder, between the cylinder-sectors, along the cylindrical surface, and also along the flat ends, as may be seen in Fig. 2, and 5 also in Fig. 6, which is a development on a flat surface of a cylindrical section taken on the dot-ted circle a a, Fig. 2, the piston-sectors being a little displaced. Thus, when the boss B makes a sufficient angular oscillation--viz., roo through sixty degrees-relatively to the cylinder, each pistoirsector will sweep through its corresponding compartment from one cyl- 1 pump, the motive power may be provided'by For the purpose of inserting the piston-piece one end of the cylinder is removable, and is the cylinder-cover Q, Fig. 1, secured in the ordinary way by bolts at the flange. The cylinder. has a central boss, Y, Fig. 1, at the end remote from the cover, which fits into a corresponding 1'e cess in the piston-boss B. By means of this boss and by keys thecylinder is secured to the main shaft A, the rotation of which it is the purpose of the engine to obtain. The piston-boss B is secured also by keys to a hollow shaft or sleeve, H, which fits over the main or cylinder shaft A. WVhile the main shaft A extends through the cylinder both ways, the

hollow shaft H extends through the cylin-- der cover end only to a suitable distance to enable it to be carried in a bearing. To pre-- vent leakag'eof steam at this point, apiece, Z, Fig. 1, is provided with spring rings kept against the piston-boss by the steam pressure and by the compressed packing in the stuffing-box X At this end the main and hollow shafts terminate in cranks'O and P, Figs. 1, 3, and 4, each secured to its shaft by a key. At a suitable radial distance, which may or may not be, but which in Fig. 3 is shown to be, the same, each crank-arm has acrankpin, 0 and p, projecting from the crank-arm, away from the cylinder. Theorank-arm]? is bent toward 0, and its crank-pin 1) projects to a distance equal to that of 0, so that each pin terminates in the same plane transverse to the axis of the shafts. The crank-pins c and p are coupled by means of two connecting-links, L

and L,, to two other pins, d, and 61,, which proj ect from another cranka drag-crank, D. (Shown in Figs. 3, 1, and 4.) This crank D turns on a pin whose axis is parallel to the previously-mentioned main shaft and set at a suitable transverse distance away from it.

The crank-pins on the drag-crank D may or may not be, but in Fig. 3 are shown to be, set at different radial distances, and this for the purpose of causing the movements of the piston-sectors relatively to the cylinder-sectors,

which take place during any half-revolution of valve to effect a suitable distribution of steam shaft.

this second shaft and transmitted through the drag-crank to revolve the cylinder and piston; or, when used as an engine, it may in some cases be convenient to take off the whole or a portion of the power through this second The ends of the second shaft or of the pin and that of the main shaft overlap one another only a short distance, if at all, so that the crank-arms O, P, and D may all make complete revolutions.

Referring to Fig. 3, it will be seen that each link L, together with the two cranks which it connects-form a combination commonly known as the drag-link coupling, and possesses the property of causing in the revolution the angle between the two cranks to vary, being at one point of the revolution a maximum, and at another a minimum, alternately. By the use of a combination of two drag-link couplings, as shown, this action may be magnified and made to take effect in causing the hollow shaft-crank P, and therefore the piston, to rotate forward and backward relatively to the main shaft-crank G, and therefore the cylinder through an angle the magnitude of which will. depend on the proportions between the lengths of the connecting-links L, the crank-arms P and G and D, and the distance apart of the centers of the shafts, this angular oscillation of piston in cylinder taking place with a continual rotation of both cylinder and piston always in the same direct-ion.

hen used as an engine, the high-pressure fluid, when introduced between one side of each of the piston-sectors and the adjacent cylinder-sector, will, in forcing them apart, cause the rotation of both in the samedirectionfor, though the pressure-force on the piston-sector one way will be exactly equal to that on the cylinder-sector the other way, yet the connecting-link workis such that the leverage of the pressure on one will be in excess of that on the other, and the engine will move in the direction of the superior moment, and the energy of the-working-fluid will exert itself with the same effect as if it had operated on a moving piston in a fix'ed chamber. That there is a difference in the leverage one way or the other may be seen, a priom', by an examination of the angles which the links L make with the crank-arms; but it may be bettion-viz., when the piston is at either end of its stroke or oscillation, then, for the instant, the speed of each being the same, the leverage of the steam-pressure is also the same on each, and we have the equivalent of what in the reciprocating engine is called the deadcenter, past which the engine must be helped either by its own stored energy of motion or with the assistance of a second engine coupled to it. One side (which is sufficient) and the outer edge of each piston-sector and the inher edge of the cylinder-sectors are caused to work steam-tight by means of parallel strips of metal being inserted between projecting sides, as shown in Figs. 2 and 6, and kept pressed toward the surfaces of cylinder and piston-boss by centrifugal force and internal springs. The steam is admitted to the cylinder through radial ports in the cylinder end remote from cover. In Fig. 1 the section of the cylinder is taken through the ports.

A circumferential section of the ports taken along the dotted circle a a, Figs. 2 and 7, is shown in Fig. 6; and Fig. 7 is aview from the valve end of the cylinder, one-half the valve being removed, the radial ports being shown in black. The port-openings are close to and on each side of each of the cylinder-sectors S, which, as shown in Fig. (3, are at the valve side cut away to provide a suitable admission port when the piston is adjacent to the cylindersector. On this cylinder end works the valve, covering and uncovering the ports on each side of the cylinder-sector alternately.

The construction of the valve V is shown in Figs. 1, 7, and 6. Fig. 7 shows a view of half the valve, as seen from the back of the valve, the other half being cut away to show the cylinder-ports. In this it will beseen that the valve consists of four radial cavities branching at right angles to one another from a central annular space, E, surrounding the boss. Sections of these radial cavities are shown in Figs. 1 and 6. Fig. 6 shows that the radial branches are flattened out on each side to give lap to the valve and form the valve-face where it works in contact with the flat cylinder end. By means of the mechanism to be presently described, the valve is caused to rotate with the cylinder, but yet make relatively to the cylinder an angular oscillation similar to that which the piston makes, butthrough a less angle. In the central position each branch of the valve overlaps equally two of the cylinderports, by preference the two which are one on each side of a cylinder-sector. When the valve turns sufficiently to uncover one of each of the pairs of ports, the steam or workingfiuid, which, as will be presently described, is supplied to press on the back of the valve, will flow through these ports into the eylinder. At the same time the cavity of each branch will be brought opposite the other of each of the pairs of ports, and allow the fluid which has done its work to flow from the cylinder through the radial cavity to the central annular space, E, Figs. 1 and 7, from which it is led by an eduction-passage, E, Fig. 4. The valve works within a stationary steamchest, .T, Fig. 1, which incloses and jackets the entire cylinder, and to which the steam is led by the branch I. The shafts pass through the stuffing-boxes K and X The steamchest has a pocket at the bottom, into which water condensed from the steam may drain, and be drawn off when necessary. By the excess pressure of the steam on the cover end of. the cylinder the back ring of. the valve forming the outer boundary of the annular exhaust-passage E is kept pressed against the casing-cover F, Fig. 1, preventing leakage of steam. The amount of this pressure may be regulated by a thrust-collar, T, on the main shaft and adjustable bearing, Fig. 1. The mo tion of the valve is derived from a drag-link mechanism similar to that employed to regulate the movement of thecpiston in the cylinder. Since the angular travel of the valve is required to be only comparatively small, a small lateral displacement of the center of the drag-crank is sufficient. This is obtained by mounting. it on an eccentric disk through a hole, in which the main shaft passes.

Fig. 5 is a view on an enlarged scale of the linkage, as seen from the valve end of the engine.

The drag-crank for the valve consists simply of an eccentric strap in two portions connected by bolts and carrying two pins, (1, and (11,, connected by links L and L, to the pins 0 and t", which project from the cranks C and V. In Fig. 1 the drag crank or eccentric-strap is omitted, and the cranks G and V are shown uncoupled; but in Fig. 4 is shown a plan of the mechanism connected up. Like as the piston is secured to a hollow shaft, so the valve is to another hollow shaft or tube, H, which also rides'on the main shaft, and to which the crank V is secured by a key. The crank O is secured to the main shaft. The valve-tube passes through the stuffing-box K The eccentric disk XV, on which the valve drag-crank is mounted, may be secured rigidly to the frame-work of the engine, or mounted in such a way that its position may be adjusted at will, as by securing it to a lever, U, Figs. 5 and 1. By this arrangement the eccentric may be put in a position suitable to give a correct movement to the valve corresponding to a reversal of the motion of the engine; or, further, the eccentric may be placed in posi' tion for ahead motionwith an earlier perform anee of its operations on the steam, and thus a variable cut-oif derived, similar to that due in the ordinary engine to Stepheusons link motion.

r The position of the lever may be regulated by a governor, so that when the engine increases in speed the governor may not, as in the ordinary way, act on a separate valve to throttle the steam, but place the lever in such a new position that the valve V may cut off the steam earlier.

Two or more engines may be coupled. Thus a high-pressure engine may be coupled with a low-pressure engine, receiving the steam from the high-pressure engine, or engines separately supplied with steam may be coupled. The manner of coupling is shown in Figs. 8 and 9, and may be described as follows: Each engine has a main or cylinder crank. O represents the crank of the high-pressure engine, and O the corresponding crank of the low-pressure engine. They are keyed on shafts which represent :for the respective engines the shaft A.

ICO

I links to a'drag-crank.

of the previous figure. Each engine has also a hollow shaft or piston-crank, P and P and these, as previously described, are coupled by Now, the main crank of one engine,being provided-with two crankpins, is caused to do the duty of drag-crank to the other engine, and similarly the other to the one, as shown in Figs. 8 and 9. Thus, in the compound engine there are two cranks with three projecting pins of one engine facing two cranks with three projecting pins of the other, the cranks being secured to shafts which are parallel to one another, but not in the same line. By employing links of suitable length to connect the cranks, as shown, an angular interval approximating to a right angle may be obtained between the dead-centers of the two engines. In Fig. 8 is also shown another proportion of lengths of crank-arms suitable to make the two strokes of the piston take referring to Fig. 1, the crank D may be carried upon a stud upon a block, which is movable in radial guides to and from the center of the shaft A. A screw to traverse the block in the guide by means of a corresponding nut is then provided and a hand-wheel on the stem of the screw. By turning this hand-wheel the engine can be started and stopped and so set as to consume the pressure-water only to the amount necessary to overcome the resistance of the load-upon the engine. Thus the engine may be regulated according to the Work it has to perform to expend a larger or smaller quantity of the high-pressure water in performing each revolution. Lastly, the engine may, es pecially when intended for use as a pump, be provided with two separate pairs of pistonsectors, each pair, though of the whole length of the cylinder, radiating from a boss of only half the length, so that half the piston-sector of one will sweep over thev boss of the other. Thus, instead of all the piston-sectors moving together, they may move in pairs independently in opposite compartments of the cylinder. The piston-bosses being secured to two hollow shafts, one within the other, to which are also secured cranks, and then the dragcrank being provided with three pins on suitably-branching arms, a linkage of the three pins'on the drag-crank with the three pins, one on the cylinder or main shaft crank, and the two piston-crank pins, may be made to cause one pair of pistons to be approximately at the center of the stroke, while the other pair is at the end, and thus obtain a more uniform delivery of the fluid pumped.

Having described in detail and shown by drawings how I propose to construct my engine, I will now point out particularly what I considertobe especiallymyinvention. While other inventors have previously described engines and pumps in which two or more pistonsectors are made by various mechanical devices to chase one another round with varying velocity in a fixed cylinder or chamber, I believe that I am the first to show how the cylinder or chamber may be attached to and caused to rotate with someof the sectors, thus securing the advantages, first, that the sectors may be in pairs in one piece, the fluid-pressures acting in a couple on them, thus avoiding axial pressures, and yet permitting of a suitable admission and rejection of the fluid; and, second, that the piston-fricton is for the further reason much diminished, because the cylinder moves to a great extent with the piston.

I claim' 1. The combination of the rotating cylinder or chamber, the sectors with which it rotates, 1 and the piston-sectors rotating alternately faster and slower than the cylinder, substantially as and for the purpose described.

2. Thecombination of rotating cylinder or chamber having a rotating piston or pistons, caused to oscillate relatively to it by a double drag-link coupling, substantially as described.

3. The combination of rotating cylinder or chamber, rotating piston or pistons, and rotating valve making relatively to the cylinder or chamber an angular oscillation, substantially as described.

4. The combination of rotating cylinder or chamber, rotating piston or pistons, and rotating valve controlled by the double drag-link coupling, substantially as described.

5. The combination of the rotating cylinder or chamber, the rotating piston or pistons, the rotating valve, and nieans'for adjusting the center of the drag-crank of the valve-controlling mechanism, substantially as and for the purpose described.

6. The combination of the rotating cylinder or chamber, its sectors, the piston-sectors rotating alternately faster and slower than the cylinder, and means for adjusting the center of the drag-crank of the piston-controlling mechanism, substantially as and for the purpose described.

7. The combination of two coupled engines, having rotating cylinders or chambers and rotating pistons, operating with relation to each other as described, and main cranks, dragcranks, and links connecting said cranks, whereby the main crank of one engine is made to perform the duty of drag-crank for the other, substantially as and for the purpose described,

' THOS. A. HEARSON. Vitnesses:

ERNEST LIDDELL, Lovatne Place, Nclc 0n Tyne, JO N DEAN,

17 Gracechwch St, London. 

